Sustainable Energy

The global population will grow from 7 to 10 billion people in 2050. The transition to sustainable energy is still too slow, which can result in climate issues, an increase of the global temperature, an increase of the sea level and an economic recession. In December 2015 the Paris Agreement on the reduction of greenhouse gases emissions was adopted by the United Nations Framework Convention on Climate Change (UNFCCC) with representatives of 195 countries. The energy consumption per capita will increase by more than 50%. As a result, the energy need will more than double. Depleting sources and environmental pollution put “Energy” at the lead of the top-10 problems that humanity has to face in the coming 50 years. SBE-Institute of Engineering aims to make a significant contribution in dealing with this problem. The research is carried out on an international level in cooperation with partners from academia and industry.

ENERGY STORAGE

One of the key issues in the (sustainable) energy field is the storage of energy because of the fluctuating supply and demand of energy in time and distance. The complexity is not only caused by the fluctuations but also by the demand of different forms of energy such as heat, electricity, fuels, etc. The field of energy storage is multi-disciplinary and requires knowledge and expertise in thermal, thermo-mechanical, thermochemical, and electrochemical processes and materials for these processes. In SBE we work on storage of heat by developing new systems using advanced phase change materials (PCM) such as nano-encapsulated PCM’s. Another research line in SBE is the energy storage in the form of liquid fuels as these fuels have by far the highest energy density compared to e.g. batteries. Examples are biofuels and solar fuels (e.g. methanol, ammonia, etc). Experimental research is carried out on biofuels from biomass via gasification, pyrolysis, etc. Solar fuels can be produced via sustainable electrons by electrochemical and chemical processes starting from CO2 and H2O as feed. Finally, within SBE a new concept for energy storage in fly wheels is developed. For this purpose advanced strong materials are developed to be able to use very high rotation speed (>500,000 min-1) resulting in a high energy density. The strength of the SBE approach is to cover the whole range of fundamental to applied research. On the level of fundamental research there is a strong interaction with UT institute MESA+. New concepts ready for commercial application in 5-10 years are completely evaluated and designed.

ENERGY TRANSPORT

As energy consumption will be growing as well as the global population, electric power will need to be transported at higher density and higher efficiency. SBE actively researches the application of superconductivity in the high-power part of the grid: superconducting cables, grid components such as superconducting fault current limiters, but also the application of superconductivity in the generation of electric power (e.g. in wind turbines). Concerning liquid fuels, LNG is getting more and more important. Methane can be considered the cleanest fossil fuel because of the relatively low CO2 emission. For transportation it is attractive to liquefy methane to have a higher energy density. However, this requires cryogenic installations and cryogenic tanks (methane at 1 bar is -160 0C). SBE works on both aspects and specifically focuses on the development of new light-weight materials that can be used in these cryogenic applications. Similarly hydrogen, as one of the potential future energy carriers, can also be liquefied for increasing the energy density. Here, again, cryogenic technologies and materials are required (hydrogen at 1 bar is – 250 0C).

ENERGY EFFICIENCY IN INDUSTRY

SBE aims to contribute to a more sustainable society through the development of clean and efficient processes for the process and food industry. We are focusing on: i) energy savings by improved separation methods, process intensification and new process designs and ii) upgrading and re-use of waste heat. New processes, equipment and advanced methods are developed to optimize functionality of application and process, and to minimize losses and environmental impact. Research includes the evaluation of the whole process chain in order to identify main bottlenecks and related scientific challenges and is carried out at proof of principle level. The experimental work ranges from high throughput screening activities to process development unit level. The research is both theoretical (including numerical analysis) and experimental. Modelling activities are carried out at multi-scale level.

RESOURCES

Biomass

Bioenergy is the single largest renewable energy source today, providing 10% of world primary energy supply. Further support for advanced biofuel research, development and demonstration is still needed to improve conversion efficiencies and reduce costs. In SBE a large effort is put in the development of flash pyrolysis for the production of advanced biofuels. Experimental research is carried out on catalytic pyrolysis, pre-treatment of biomass by washing, separation and upgrading of the pyrolysis products, etc. Also the application of biofuels in gas turbines, engines, boilers is investigated by studying both the atomization and combustion processes. For this purpose SBE has well-equipped laboratories with high-throughput screening equipment, bench-scale process units and pilot-plants. Other thermochemical processes that are developed are gasification, supercritical water gasification, torrefaction, hydrothermal conversion, combustion, etc.

Wind

Wind energy is playing a crucial role in the transition from fossil energy sources to sustainable renewable energy resources. The major aspects in the current developments are the continuous upscaling of wind turbines to generate more power leading to larger blade sizes where aerodynamic and mechanical design becomes a challenge, as well as the prediction of the interaction between turbines in wind parks and optimal positioning accounting for the wake effects. This requires advanced predictive tools and extensive validation. We develop fast and efficient multilevel panel methods for analysis in the early design phase combining good accuracy to low computational cost. In addition to this medium fidelity method SBE develops high performance and highly scalable numerical schemes for efficient modeling in the later design stages of modern wind turbines. Wind turbine noise is a major restriction for placing and upscaling of wind turbines. Moreover, to reduce noise, wind turbines are sometimes operating in a lower power production setting, leading to a loss in revenue as a result. Aero acoustics is a challenging field of research because of the link of the small scale fluctuations of the noise in combination with large scales of the aerodynamic flow field. SBE focuses on the development of semi-analytical methods and their experimental validation for silent design using the Twente A2 Aero-acoustic Wind Tunnel facility exploiting Particle Image Velocimetry (PIV) and advanced microphone arrays methodologies.

Waste heat

Waste heat is a by-product of an industrial process or from the built environment. This, in general, low-temperature heat can be reused via heat pumps or heat engines producing heat, cold or electricity. In SBE research is carried out on thermo-acoustic and magneto-caloric heat pumps. SBE focuses on 1) the development of numerical models for the design of this new generation heat pumps, and 2) the application of new materials and configuration to enhance the heat transfer. This research is closely connected to our research on Urban Energy focusing on the optimization of the energy systems in the built environment. The research is concentrated on the whole value chain from proof-of-principle to technology development.

Solar

Solar research at SBE aims at achieving a better performance and better integration of solar energy technologies in photovoltaic (PV) modules, PV systems, products, buildings and local infrastructures such as smart grids. This requires a design-driven approach which is strongly embedded in the disciplines of mechanical engineering, industrial design engineering, electrical engineering and physics. Research comprises among others outdoor test facilities for PV modules and PV systems, data processing, simulation tools in the context of virtual reality and design and prototyping activities. Building integrated PV, product integrated PV, solar charging of vehicles and PV in smart grids are research topics that are connected to the research agenda on sustainable urban innovations of ARISE and can be supported by advanced photovoltaic materials research within the MESA+ institute.